10. Caterpillars
Caterpillars in Brazil need to be on the lookout because if they are particularly unlucky, they could find themselves being controlled by a completely different animal. About 80 times a year, the parasitoid wasp, Glyp-tapanteles, lays its eggs directly into young caterpillars. These eggs soon hatch, and the larvae feed on the caterpillar’s bodily fluids, inside the caterpillar, until they have fully developed. They then eat their way out of the caterpillar like something out of alien, and latch onto a branch or leaf, and then form a cocoon around themselves to turn into a wasp.
Now, after all of this you might think the caterpillar would be dead, but it’s not. It’s weakened body starts to act as a bodyguard for the cocoons, seemingly controlled by the invaders. Rather than going about its usual day to day business, it stands over the cocoons to protect them. It only finally dies once the adult wasps hatch and they have no further use for it.
Experiments at the University of Viçosa found that this protection makes the wasps far more likely to hatch safely. The caterpillars have been seen to protect the cocoons from predators like stink bugs, and found that the survival rate of protected cocoons was more than double that of unprotected ones. The caterpillars, though, suffer a far more painful fate. It’s not entirely clear the point at which they actually die, but they definitely act like zombies for the time between the larvae burrowing out of their bodies and hatching from their cocoons.

9. Fish Tongues
This next real life zombie isn’t an entire creature, but instead one particular organ- a fish’s tongue. The takeover happens when a group of creatures called Cyma-thoi-daes, that live in tropical and subtropical waters, swim into a fish’s mouth through its gills, and start to eat the tongue.
Once the organ is completely devoured, they form together to create a structure that replaces it, facing outward, and begins to function as a tongue. Sneaky right?? Of course, this affects the host fish’s ability to feed properly, and results in lower blood counts in infected fish than uninfected ones. If this all sounds too horrible, though, you’ll be pleased to know that they aren’t able to do the same to humans- so you won’t need to be too concerned the next time you have fish for dinner and wonder whether it has its real tongue.

8. Carpenter Ants
Ants are found most places in the world, and there isn’t necessarily anything that immortal about the carpenter ant. Usually when they die, they stay dead! This isn’t always the case in the jungles of Thailand, though, where their corpses are known to keep moving- and it’s all because of a fungus!
The spores infect the ants without them knowing, and by the time it has taken hold it’s too late. In a matter of days the ant becomes the host. The spores take over and the host feels a compulsion to climb as high as it possibly can. Just before it fully dies, the body becomes a zombie and clings onto its perch, high up above. By now, the fungus has matured, and begins to break out through the ant’s back, and shower spores across a wide area on the ground for the cycle to start all over again.
This fungus, from the genus Ophio-cor-dyceps, can actually infect a number of species including butterflies and cockroaches, but the effects are most obvious when seen in ants. In some parts of Thailand, it affects so many ants that there are ant graveyards with hundreds of lifeless bodies hanging off leaves and branches. It’s as if “A Bug’s Life” were turned into a horror story.

7. Japanese Tree Frogs
There’s another fungus called Batra-cho-chytrium dendro-batidis that affects the behavior of animals in an attempt to help spread further. This time instead of creating decrepit zombie-like creatures, it turns its hosts into sexually appealing zombies.
The host in question is the Japanese Tree Frog, native to wetlands in Asia. It was noticed that although the frogs were being infected by the fungus, they weren’t dying off. Instead the main difference that could be measured was that their mating calls changed. They became faster and longer, which means that they become more attractive to potential mates.

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